Or Operator Precedence

What's the difference between || and or in Ruby?

Let's look at an example to find out. First, let's start with some boolean variables:

> a, b = false, true
=> [false, true]

Now, let's try the different or operators:

> a || b
=> true
> a or b
=> true

Cool, they seem to work as expected.

Finally, let's capture the result in a variable:

> c = a or b
=> true
> c
=> false

But why is c false and not true? Operator precedence. The assignment operator (=) takes precedence over the or operator causing c to be assigned to the value of a (false) before or'd with b.

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